An aqueous effluent containing CO.sub.2, H.sub.2 S and NH.sub.3 can be supplied to a stripping column (total stripping column), from which a mixture that is rich in NH.sub.3, CO.sub.2 and H.sub.2 S is withdrawn as a head product. This mixture is separated in at least one additional stripping column into a mixture that is rich in NH.sub.3 and a mixture that is rich in the sour gases CO.sub.2 and H.sub.2 S, and the mixture which is rich in NH.sub.3 is scrubbed with liquid ammonia.
Such a process is known from German patent No. 2,527,985 and the corresponding U.S. Pat. No. 4,060,591.